The working principle of a Universal Testing Machine (UTM) is centered around evaluating how materials respond under various types of load, such as tension and compression. The process begins with test specimen placement, where the material sample is clamped securely between two fixtures—grips for tensile tests and platens for compression tests. In a tensile test, the grips pull the specimen apart, while in a compression test, the platens apply force to squeeze the sample from both ends. After the specimen is fixed, the application of load takes place. This is achieved either through a motor-driven screw mechanism in electromechanical UTMs or a hydraulic actuator in hydraulic UTMs. The crosshead, which moves vertically, applies force depending on the test type, and a load cell precisely measures the force being exerted.

As the load is applied, the material begins to deform, which leads to the measurement of deformation. Instruments like extensometers or strain gauges are used to record how much the material stretches during tensile testing or compresses during compression testing. These instruments provide data on strain, while the applied force is recorded as stress. The UTM’s software then generates a real-time stress-strain curve, a graphical representation that highlights the material’s key mechanical properties. This includes the elastic limit, yield strength, ultimate tensile strength (UTS), Young’s modulus, and the fracture point. Finally, the test termination and result analysis step occurs automatically when the material either breaks or reaches a predefined load limit. The software compiles all test data for detailed review, offering engineers precise insights into the material’s performance characteristics. This makes Universal Testing essential in quality control, research, and material certification processes across industries.